Gestra valve

When a certain static pressure difference is established (upstream pressure minus downstream pressure of the valve), check valves with springs or counterweights begin to open.

This will generate an opening force (pressure difference x cross-sectional area of the valve) that acts on the closing force.

When the opening force exceeds the closing force, the valve element opens (opening pressure). The necessary opening pressure depends on the spring tension or weight of the counterweight, installation position, and size of the check valve.

At the start-up of the factory, static pressure will first be established between the pressure generator and the check valve.

Once the opening pressure is reached and the closing force is exceeded, the volumetric flow begins.

The pressure drop upstream of the check valve causes the closing force to exceed the opening force again, resulting in the valve closing.

This process will be repeated until the volumetric flow rate is large enough that the closing force is no longer strong enough to close the valve due to the additional dynamic pressure difference.

According to the volumetric flow rate, the check valve can be fully opened or only partially opened. During partial opening, i.e. when the volume flow rate decreases, a clicking sound may occur.

This is caused by the valve disc, cone or disc hitting the valve seat. It is possible that what you hear is not a clatter, but a high-frequency buzzing sound.

Continuous noise is a clear sign of oversized check valves; The selection of valves did not meet the requirementssatisfyThe status cannot meet the requirements of the factory.

If the pressure drop at full load becomes too large, the possibility of using valves with smaller nominal sizes will no longer be provided.

Sometimes, noise can only be heard during startup or shutdown, or only under partial load.

Then, the valve is only oversized during these operational stages and can be solved by reducing the closing force, such as by using weaker springs or reducing counterweights.

Even valves without any springs can be used - in vertical pipes that flow upwards.